Evaluate the following expression when $y = 9$ and $x = 2$. $5$ $y$ $ + 6$ $x$ $ - 6$
Answer: Substitute $9$ for ${y}$ and $2$ for ${x}$ $ = 5{(9)} + 6{(2)} - 6 $ $ = 45 + 12 - 6 $ $ = 51$